Iron oxide coating fenton-like catalysts: Preparation and degradation of phenol

The iron oxide coating Fenton-like catalyst on Ti alloy was successfully prepared in silicate electrolyte via micro-arc oxidation. The surface morphology, crystal structure and phase composition were studied by SEM, XRD and XPS. The results indicated that the as-prepared coating included the rutile TiO₂ (R-TiO₂), and amorphous Fe₃O₄ which was analyzed by XPS. The SEM images suggested that after the addition of K₃[Fe(CN)₆] in the electrolyte, the surface roughness and average pore size of the as-prepared coating were increased. The Fenton-like catalytic activity of as-prepared coating was investigated by degradation of phenol. What's more, the influences of K₃[Fe(CN)₆] content, phenol concentration, H₂O₂ dosage and pH value on phenol degradation were also studied and finally the optimal degradation condition was confirmed. Under pH 3.0, 30℃, H₂O₂ 6.0 mmol·L^-1, phenol 35 mg·L^-1 and K₃[Fe(CN)₆] 10 g·L^-1, 90% phenol could be removed. The effect of degradation temperature on degradation efficiency was also evaluated and the reaction kinetics under different temperature were also studied. The activation energy of Fenton-like degradation of phenol through Arrhenius equation is 96.9 kJ·mol^-1. Finally, the stability was studied and the stability degradation was also analyzed.